For those who have not given themselves the treat that is a viewing of Ron Moore's Battlestar Galactica, Gaeta was essentially Lieutenant Sulu. He made the ship do FTL jumps when needed, and read out sensor readings and things to the crew. Here's what happened. Spoilers!

Over time, he became more and more important. He wound up serving as the Chief of Staff to the President during the Cylon occupation. Accused of collaboration, he was nearly executed. As with many people on the show, the innocent trusting man he was at the start became gradually corroded and dirtied. He was shot in the leg, and had his leg amputated above the knee. Unfortunately for him, the humans had run out of painkillers by this time, and he had to endure both the operation and aftermath without any anaesthetic. He sang the above song to himself whilst recovering and struggling with phantom limb syndrome, an affliction he lived with until seconds before his death.

Ultimately, Gaeta tried to do what he thought was the right thing, and it led him to a dark place. As Adama began to cooperate more and more with the Cylons, Gaeta become convinced that it was folly and would lead to the extinction of humanity. He participated in a mutiny against Adama, which failed. Gaeta and the other mutineers were lined up against a wall and executed by firing squad.

His final words? He glances at his leg and says "It's stopped."

Give a man a fire, and you keep him warm for a day. SET a man on fire, and you will keep him warm for the rest of his life...